Two phase III studies of KX2 391 ointment meet primary endpoints in actinic keratosis

Almirall and Athenex announced that an oral presentation reporting the results from two Phase III studies of KX2 391 ointment in the treatment of actinic keratosis (AK). Both Phase III studies, KX01-AK-003 and KX01-AK-004, achieved their primary endpoint, which was defined as 100% clearance of the AK lesions at Day 57 within the face or scalp treatment areas. Statistical significant difference in 100% clearance was demonstrated for all subgroups analyzed in both studies based on treatment location (face or scalp), gender, age (below 65 and older than 65 years old), number of baseline AK lesions (4-6 versus 7-8 lesions) and also skin type. Compliance to 5-day of self-treatment was over 99% for both studies.

Safety results showed that KX2-391 ointment was well tolerated. Adverse events were few. Treatment related adverse events were mild to moderate application site symptoms, such as pruritus or pain. There were no serious adverse events or early discontinuations due to study drug related adverse events. Local skin reactions (LSR: erythema, flaking/scaling, crusting, swelling, vesiculation/pustulation, erosion/ulceration) were mostly mild to moderate.

The one year follow up of patients who had complete responses is ongoing and is expected to be complete in the second quarter 2019. Athenex plans to submit a request to the U.S. FDA for a pre-NDA meeting to discuss the data and regulatory submission timelines. The results were featured in the Late-Breaking Research: Clinical Trials session at the 2019 American Academy of Dermatology Annual Meeting.